Crankshaft chuck



Jan. 30, 1940. w. F. GROENE ET AL 2,188594 CRANKSHAF'I CHUCK Filed Nov. 28, 1938 2 Sheets-Sheet 2 WILLIAM F. GROENE Patented Jan. 30, 1940 UNITED STATES PATENT OFFICE CRANKSHAFT CHUCK Application November 28, 1938, Serial No. 242,705

7 Claims.

This invention pertains to chuoking mechansm which is adapted to grip cranks'nafts by means of peripheral machined localting areas prepared on webs of the crankshaft as shown, for example, in our co-pending application Serial No. 121,509, filed January 21, 1937.

An object of this invention is to provide a. chuck with a fixed arcuate supportin g and 10- cating abutment which is adapted to engage a machined peripheral locating area on a web of a crankshaft and having a cooperating clamping means to hold the shaft in proper engagement with said locating abutment.

Another object is to provide a fixed arcuate locating abutment in the chuck body which is adapted to engage a finished D ripheral locating area on a. web of said shaft and to provide a positive driving means and a, clamping means in conjunction with said abutment to maintain the crankshaft in proper engagement with said chuck abutment.

Still another object is to provide a pair of axially spaced arcuate abutments in the chuck body adapted to engage peripheral locating areas on a pair of webs of a crankshaft and to provide equalizing clamping means in conjunction with said abutments to maintain proper engagement of the crankshaft with the locating abutments in the chuck.

Further features and advantages of this invention will appear in the course of the following description of the drawings in which:

Figure I is an end elevation of the chucking device gripping a crankshaft, having machined peripheral locating areas, in a ring gear of a double center drive lathe.

Figure I[ is a dametral section substantially on the line IIII of Figure I showing the crankshaft chucked in the ring gears of the double center drive 1athe.

For illustrative purposes the invention is shown applied to a double center drive crankshaft lathe, for example of a character shown in Patent 2069107 dated January 26, 1937, having a pair of ring gears l and associated cutting tools T for machining the line hearing portions L of a crankshaft C. The crankshaft C is usually steadied at its ends by centers 2 carried in appropriate tailstocks 3, though this is not essential to the proper operation of the chucking devices in the ring gears In each of the ring gears l are provided flanges 4 and 5 which properly locate the segmental chuck body 6 which is fixed to the flange 5 by bolts 1 and dowe1 pins 8. Fxed in the body 6 is the arcuate locating bushing 9 which has its semi-circular locating surface I0 arranged concentric with theaxis of rotation I I of the crankshaft C in the lathe. The crankshaft C has the periphery l20f its various webs I3, I 4, [5 and [6 accurately machined relative to the axis ll and. dimensioned to accurately fit against the locating surfaces |0 of the bushings 9 to thus accurately locate the crankshaft in the lathe.

A clamp I'| pivotally mounted by a pin I 8 on the body 5 has a transverse equalizer bar I9 carried in a slot 20 of the clamp which is maintained therein by a suitable pin 2! fixed with clamp I| and passing through a clearance hole 2! in the bar I9. The bar I9 has a fulcrum point 22 which bears against the surface 23 of the slot 20 to permit free rocking of the het so that its work contacting ends24 firmly engage the rough surfaces of the various webs I3, [4, and L5, [6 to ho1d the webs in firm engagement with the arcuate locating bushings 9. Suitable eccentric clamping means 25 actuating the latch 26 in amanner fully de5cribed in Patent 2,030,020 dated February 4, 1936, serves to force the clamp l'| against the work.

In order to prevent rotation of the crankshait C on the locating bushings 9 under the turning forces exerted by the toois T, fixed driving blocks 21 are mounted on the body by the screws 28 and abut against the webs 29 and 30 of the crankshaft to provide a positive driving force intermediate the respective webs l3-|4 and I5--|6.

Having thus fully set forth and described our invention, what we claim and desire to secure by United States Letters Patent is:

1. In a chucking device for orankshafts, a rotary chuck body, a fixed arcuate locating abutment in said chuck body adapted to engage a peripheral locating area on a web of a crankshaft to be gripped in said devce, clamping means for holding said crankshaft in engagement with said abutment, and fixed driving means in said body to positively rotate said crankshaft with the rotation of said chuck body.

2. In a chucking device for crankshafts, a rotary chuck body, a flx ed arcuate locatng abutment in said chuck body adapted to engage a peripheral locating area on a web of a crankshaft to be gripped in said device, clamping means engaging the webs having said locating areas for holding said crankshaft in engagement with said abutment, and fixed driving means in said-body to positively rotate said crankshaft with the rotation of said chuck body.

3. In a chuckng device for crankshaits, a rotary chuck body, a. flxed arcuate locating ebutment in said chuck body adapted to engage peripheral locating areas on a. plurality of axielly spaced webs of a. crankshaft te be gripped in 5 said device, clamping means engaging the webs having said locating areas for holding said crankshaft in engagement with sa.id abutment, end. fixec drving means in said body to positively rotate sad crankshait with the rotation of seid 19 chuck body.

4 In a chucking device ior cranksha.fts, a rotary chuck body, a flxed arcuate locating abutment in sad chuck body adapted to engage perpheral locating areas on a. pair of axially spaced 15 webs of a crankshaft to be gripped in said device, equalizing clamping means engaging the webs having said locating areas ior holding said crankshaft in engagement with said abutment, and fixed drivng means in said body to posigo tiveiy rotate said crankshaft with the rotation of said chuck body.

5. In a double center drive lathe, a. pair of synchronousiy rotatable ring gears, chucking devces in said ring gears ha.ving fixed axcuate 251ocating abutments adapted to engage peripheral locating areas on axially spaced webs of a crankshaft to be chucked in said lathe, equaiizing clampng means engaging the webs having said locating areas ior holding said crankshatt in engagement with said abutments, a.nd driving means in said ring geen; te positively rotate said crankshaft with said geen.

6. In a double center drive la.the, a pair of synchronously rotatabie ring gears, chucking devices in said ring gears each having fixed arcuete locating abutments adapted to engage peripheral locating areas on axally spaced pairs of webs of a. crankshaft to be chucked in said lathe, equalizing clamping means in each ring gear' engaging the webs having said locating areas for holding said crankshaft in engagement with said abutments, and driving mea.ns in said ring gears to positively rotate said crankshat with said gears.

7. In a double center drive lathe, a. pair of 'synchronously rotatable ring gears, chucking devices in said ring gears ea.ch having fixed a.rcuate locating abutments adapted to engage perlpheral locatng areas on axially spaced pairs of webs of a crankshaft to be chucked in said lathe, equalzing clamping means in each ring gaar engaging the webs having said locating area.s for holding said crankshaft in engagement with sa.id abutments, and driving means engaging other of the webs of said crankshaft to positively rotate said crankshait with said gears.

WILLIAM F. GROENE.

WALTER R. MEYER. 

